#precalculus

1 messages · Page 70 of 1

dire ginkgo
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WE GOT THIS!!!

mystic sluice
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did you not get any practice assessments on ap classroom?

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GL everyone

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bruh my teacher sent the practice the night before the examsully

dire ginkgo
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😔

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I have the unit circle in my head, mastered frq 3 very familiar with the other 3 frqs, my only flaw is polar and rectangular equations

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What y’all think I would get

mystic sluice
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5

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if not 4

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ig if you are strong on everything else you should get a 5

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polar is less than 1/3 of the exam anyways

dire ginkgo
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Id be fine with a 4 but I need that 5, I’m very cooked for physics I need a tutor

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Ap physics 1

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Test is this Friday and I’m screwed

viscid thistle
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Hey guys, anyone online?

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I'm doing a practice sheet for calculas, indefinite integration. If anyone interested in solving with me, dm me

wary agate
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I got one question for the ap test tmmr

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,rcc

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,rccw

obsidian monolithBOT
wary agate
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Nice

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Ok but basically this question it’s obvious that f does not have an inverse

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But when I go to explain it I can’t only say it doesn’t pass the horizontal line test

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What can I say to get the frq point

winter comet
wary agate
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So just give two points pretty much

winter comet
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which I can't see but I assume has a contradiction

wary agate
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Ok

warm cove
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AP exam is over, did a lot of studying yesterday and I think it paid off as I have confidence I did a good job, the questions were really easy compared to the ones my teacher gave out so I was better prepared

dire ginkgo
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I just finished

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No way I didn’t get a 5

mystic sluice
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did anyone remember getting 400pi for one answer

marsh cipher
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how do i start on this? im hella lost lol

glass solar
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i dont know but i think The area of the rectangle is the product of its width and height

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the windth of the rectanle is x from the lower right corner to the vertical line at x)

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the high of the triangle is f(x) x to the power of fourth

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the function is A(x)=xx(to the power of fourth)=xto the power of fifth

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o maximize 𝐴 ( x ) = 𝑥 5 A(x)=x 5 , you would use graphing tools or a calculator to analyze the behavior of the function over the given interval [ 0 , 6 ] [0,6].

marsh cipher
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answer is 6x^4-x^5 then use desmos to find maximum area, it was x(6x^3+x^4)

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i think ill just ask professor tomorrow to elaborate it

uncut mantle
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bro the min max quadratic question was so dumb

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i didnt realize that you could just say that the max was the end of the domain

mystic sluice
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Broo fr

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I said something dumb

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I thought they ignored the domain on that question

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I thought the max was somewhere in between the domain

mystic sluice
uncut mantle
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1/800 should be c I think but it can vary

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D is 0

zinc herald
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How do you determine rational points of an elipse on a graphing calc

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I have hw that says "graph the relations on a graphing calc and identify 4 additional points on the graph whose coordinates are rational"

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and then gave 25x^2+9y^2=255

long tapir
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Im a bit confused as to how to find the answer to this problem

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Mainly because of the square root

willow skiff
zinc herald
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yes

willow skiff
zinc herald
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just to make it easier

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let X=5x and Y=3y

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so you get X^2 + Y^2 = 255

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and now it's just a circle

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and I can divide by 255

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but IDK what to do

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it's not 225

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it 255

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15^2=225

willow skiff
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oh right

zinc herald
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I am leaning on that their is no solution

willow skiff
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ask your teacher then

zinc herald
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sure

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also, when I rechecked the hw

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it said to skip this specific question

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so I think the textbook might have made an error

willow skiff
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I bet they meant 225 and not 255

zinc herald
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yeah

willow skiff
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alr cool

zinc herald
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but now I kinda want to prove that their is no solution

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but apparently that requires like Diophantine stuff

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😭

willow skiff
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but it's not too bad once you know the technique

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255 is divisible by 3 which makes a lot of sense considering squares modulo 3

solid shuttle
cedar idol
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Hey, I'm struggling with this one calculus & vectors (high school) problem, is anybody able to help me out with it? I don't know what I am doing wrong. My work is attached to this text, Thank you.

"A pilot in an airplane with an airspeed of 1000km/h wishes to fly to a city 2000km due east. There is a wind blowing from 025 degrees at a speed of 100km/h.

In what heading should the pilot steer?"

solid shuttle
empty otter
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are 3d vectors in precalc or not

viral junco
willow skiff
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depending on curriculum they can be

spice perch
viscid thistle
brisk glen
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<@&268886789983436800> This should be the final one

zinc herald
long tapir
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Yep

open dawn
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someone teach me calculus and get $0

zinc herald
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lmao

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watch 3b1b

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  • khan acedemy if you want problems
zinc herald
long tapir
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Alr i got it i believe

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Thank you!

zinc herald
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np

vale spindle
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do you guys watch youtube video courses on precalc? is it good enough on its own to self study?

willow skiff
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Khan Academy is a decent source of practice

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but textbooks will have more in-depth questions

elfin niche
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I am doing piecewise, I sorta understand how to do the x portion of the graph but not the y portion, do I just swap the x with a y?

uncut mulch
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no, you shouldn't be swapping x with y

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you sub the value you chose for x into x (for that piece)

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and the way you're setting up the tables implies you aren't using the proper x values

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where's 4 and 9 coming from in the second table?

elfin niche
uncut mulch
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what numbers were you substituting with?

elfin niche
uncut mulch
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2 * 8 - 4 would be 12 though

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but regardless

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you should have labels on your columns

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with values of x you're using in the left column

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and the respective f(x) value in the right column

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f(x) = -x-4 for x<=0

__________
-5   | 1
-4   | 0
-3   |
-2   |
-1   |
0    |```
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and similar idea for the other piece

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if you want to make a table of values to get your points

elfin niche
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I think I get it, so I plug in a number that matches the piece, and what that number equals when plugged in is the y value

uncut mulch
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yes

elfin niche
hushed sphinx
uncut mulch
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lol shit.

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was half awake

elfin niche
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Am I supposed to multiply the number by 3 since it is greater than zero for the last piece?

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Also where did I go wrong with number one?

vale spindle
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dosen't -x-4 tell you the y intercept is on minus 4?

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and -x is -1/1 or 1/-1 i think

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so you would move indefinetly 1 y 1 x and depending on the direction the y or the x would be the negative one

prisma aurora
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guys im new here but i have a quick question to those already in pre cal

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rn im in alg 2 and ima take pre cal over the summer thru UTHS any tips or some ? bc ngl im not that good at math but i needa get ahead i lwk slacked alot in alg 2

lethal sand
distant oasis
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Can someone else I’m not sure how I would graph

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I’m very lost

inner viper
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For first one, imagine point -3 and then point it anywhere

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And then make an arrow to it until your graph ends to -∞

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Do these for others too

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Since we don't know what's infinity, you need to show that it's going forever

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With a ray

coarse thorn
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Step 1: draw the given asymptotes
Step 2: follow the limits given in the question

distant oasis
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Would I need to put points to where I put it

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Like close or open dots

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For the x=1 and y=-3

coarse thorn
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Open dot is for points where function is undefined

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No need for it here

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Open desmos

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(-3x+1)/(x-1)

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Could be the fn

coarse thorn
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@distant oasis

mild inlet
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Do you guys know if a logarithm can be written with just arithmetic math in 1 mathematical formula

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It sounds impossible but surely it's possible if floor division and absolute values are allowed

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because I was told by AI that it's not possible since a logarithm requires conditions (if/else) but surely that can be simulated with floor division and absolute values

safe basin
mild inlet
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Basically I'm allowed only floor division, which u can use to simulate the absolute value

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But in general, no if statements, no for loops, no special functions or classes, no domain and range restrictions, nothing

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just floor division, normal division, and the other remaining arithmetic operations

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if anyone has a solution to this (even tho it sounds impossible) pls let me know ill pay u $10

safe basin
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but you’ll probably find someone to help here anyways

mild inlet
hushed sphinx
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With those tools, it sounds like you can only make functions whose growth matches a rational function, which logarithms don't.

mild inlet
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but cant you simulate if and else conditions using floor division?

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i swear u can

hushed sphinx
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I'm not sure exactly what "floor division" is, but assume it is division with the quotient truncated to an integer.

mild inlet
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ya

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thats what i mean sorry, floor division that truncates to an integer

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so within my environment i can use decimals and integers, and normal division and truncated division

hushed sphinx
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It won't help you with the argument I have in mind, because even if you can build if-then-else, you can only have finitely many cases anyway.

mild inlet
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But to be honest I only need a working if-else statement to do this

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because i already have a previous version of a logarithm using only arithmetic calculations that also uses if else statements using step wise reduction, if i can normalize the if statements to just arithmetic math with the truncated division it can be possible

hushed sphinx
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If you only need your logarithm function to work for a bounded range of inputs, you can hope for an approximation that works well there.

mild inlet
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decimals will be too complicated, so whole numbers is fine and no zero since i think logs dont allow zero

hushed sphinx
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Unfortunately the integers are not a bounded range ...

mild inlet
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hmmmm

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like A - B?

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ok i can do 1 - 999 i guess

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or like 1 - the integer bit overflow square root or something idk lol

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log i mean

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can someone help me i have lots of money ill pay u $50 if anyone has a solution to this

hushed sphinx
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Well, if you have an upper bound for the input and you're satisfied with an approximate output, then there are no theoretical obstacles -- thanks to the Weierstrass approxiation theorem, you can approximate the logarithm arbitrarily well by polynomials of sufficiently high degree.

mild inlet
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yeah I was thinking polynomials

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wait

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ok yeah polynomials

mild inlet
hushed sphinx
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I won't be able to tell you which polynomial, unfortunately.

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These were only strictly theoretical musings.

mild inlet
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bro what does that mean

mild inlet
chrome ether
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!nogpt

tender questBOT
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Please do not trust ChatGPT or similar AI tools for mathematical tasks, as they often generate output which "sounds correct" but has numerous factual or logical errors. Use of these AI tools to answer other people's help questions is strictly against server rules (see #rules).

muted moth
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@mild inlet as mentioned all of the way at the beginning of the thread, we need to know the range of values you expect to be fed into this function in order to give you anything reasonable. But if you can give me a minimum value, a maximum value, and a maximum tolerance, I can give you back a polynomial or rational function that will give you your result.

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Alternatively, if you wish to do it yourself, the procedure I was going to use is known as the Remez algorithm

The Remez algorithm or Remez exchange algorithm, published by Evgeny Yakovlevich Remez in 1934, is an iterative algorithm used to find simple approximations to functions, specifically, approximations by functions in a Chebyshev space that are the best in the uniform norm L∞ sense. It is sometimes referred to as Remes algorithm or Reme algorith...

mild inlet
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minimum values for values B and X are 1, it cant accept any values that give an error

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so log1_1 should be whatever the standard logarithm function gives

muted moth
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Ignore the base

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You can use change of base formula

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What are the allowed values of x?

mild inlet
mild inlet
muted moth
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You figure out what values are likely to go into the function, and which values you do not care about

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Or alternatively, you have to come up with a method of mapping larger values into the smaller range via a continuation somehow

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Like ln(xy) = ln(x) + ln(y) in your case, if you have access to both ln(x) and ln(y) then you can figure out ln(xy)

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For instance, if you decide you want to implement log_2, for inputs between 1 and 2, then if you're given x = 6.3 you would need to divide by 4 to get x into the proper range. Fortunately, for floating point numbers, you have the exponent, and if you can extract it you know how much you need to divide or multiply your input by

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Oh, I should take this into the thread

viscid thistle
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Hi, is there anyone who speaks spanish?

hushed sphinx
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No, the Spanish language is a hoax; nobody actually speaks it.

fiery crest
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I'm really really behind in trig and I have a midterm Friday. I've tried to watch the videos my instructor gave but I don't understand what he's doing and it's taking hours to solve one question at a time. Idk what to do anymore

alpine shore
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@fiery crest Can I help you please?

bleak forge
viscid thistle
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So there's 2 questions I got wrong on my final for pre cal

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The first was prove
secx-1/tanx = secx+/tanx

It's probably easy but verifying solutions stump me

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And fins sin2x if tanx is 24/7 cos>0

viscid thistle
zenith elbow
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Can anyone help me? I have to do a 10-minute oral in maths and I'm doing it on Gabriel's horn , but it's too short.

hushed sphinx
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That sounds like a difficult topic to do justice to without calculus.

tawdry ibex
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hi
peles help me
I have a problem. I'm trying to solve time flexibility with math. We have a vision of a series of numbers that are repeating or a series of decimal numbers that are not divisible by anything at all.
p= 2X *9m =- 11
11 -= 0m + mp2 - 29 = 2.7580088765936458
OM = 0 -9 *1.2 + 0.4
mp = 8 + 7 * 78 - 3
and
x =?
m == X-2 * 82 ms

hushed sphinx
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Please don't crosspost the same question between all the pre-university channels. I cannot follow exactly what you're saying, but it looks like responses should probably be in #prealg-and-algebra.

slate fox
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can someone please help me with this

sterile pulsar
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yeah sure

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so you wanna ask something specific? Or the whole problem set?

brazen sedge
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Can someone explain to me what a log is 🙏

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(What(is(a(log(x)))))

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Hope I did that right

safe basin
brazen sedge
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I don’t get the fancy wording 😔

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Actually nvm

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Just googled it

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I understand it now

safe basin
brazen sedge
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❤️ ❤️ ❤️

willow bear
meager stump
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I don't remember the definition but I think inverse of a power? (not as in negative exponent)

granite wolf
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<@&286206848099549185> should I just differentitate both sides?

hoary iris
granite wolf
#

sameer bansal

hoary iris
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english! @granite wolf

granite wolf
hoary iris
granite wolf
#

it's from a book called sameer bansal

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@hoary iris did you gave mains?

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or are you a 26 tard?

hoary iris
hoary iris
granite wolf
granite wolf
granite wolf
hoary iris
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btw who are you? and how do you know about me? @granite wolf

granite wolf
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i had a chat with you

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a few months ago

hoary iris
granite wolf
#

along with a couple of other dudes

granite wolf
hoary iris
#

wht happen to your pfp?

granite wolf
hoary iris
granite wolf
hoary iris
#

what made you cam here?

dusty jay
elfin niche
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I don’t understand how to pick the points for the piece wise

willow bear
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ok let's just crop away the black bands that are like 3 times as tall as the image itself

willow bear
#

in your case that's x=1

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so pick that and some other easy values around that

violet stratus
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hi

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can you explain fx a bit

elfin niche
willow bear
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you should include 2 itself yes

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and also something to the left of 2 and something to the right of 2

violet stratus
#

can anyone explain fx a bit

elfin niche
violet stratus
#

yes

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i am new

elfin niche
violet stratus
#

okay

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i am new to the concept

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btw which grades r included in precalculus

elfin niche
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well for me precalculus is a senior and junior high school class and they also teach it in some colleges

violet stratus
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okay

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that means i am in the wrong group

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which group is for 8th graders

elfin niche
violet stratus
#

okay thanks

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sorry for causing any trouble

elfin niche
violet stratus
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is it still okay if i join this group

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i just really like math

elfin niche
violet stratus
#

thanks

high pelican
elfin niche
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I’m getting a bit doomer about math again

hoary iris
#

Is $\lim_{x \rightarrow 0}(log_{a}x) = -\infty \ \forall \text{a}\in(0, \infty)$?

obsidian monolithBOT
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Monkey•D•Luffy

hoary iris
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why not? @willow bear

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,w lim_{x->0} log_{a}(x)

obsidian monolithBOT
hoary iris
willow bear
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it depends on whether a < 1 or a > 1

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if a > 1 then the limit is -∞ but if a < 1 then it's +∞

hoary iris
merry widget
willow bear
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he was asking for the limit as x goes to 0 so no it is the right way around

crisp thicket
#

sup

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i like math

high pelican
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Yo

polar laurel
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@wooden nymph HI BRO

wooden nymph
#

hibrother

zinc herald
#

can the parabola be considered a special case of the hyperbola just like the circle is considered the special case of an ellipse?

river drift
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as conic sections they are distinct, the parabola is the case in between the ellipse and the hyperbola

prisma aurora
#

can someone help me with some pre cal

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i genuily dont understabd the algrba behdin it

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𝑏(𝑥) = 1 /𝑥+3 on [1, 1 + ℎ] - how to find the avg rate of change, ion get the algebra behidn it

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or Let 𝑓(𝑥) = 1
𝑥. Find a number 𝑐 such that the average rate of change of the function 𝑓(𝑥) on the interval
(1, 𝑐) is − 1/4.

willow bear
obsidian monolithBOT
prisma aurora
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second option the bot provided

willow bear
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it was me invoking the bot not the bot itself :P

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anyway

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...what exactly is unclear to you?

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do you get lost in the sauce when simplifying?

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or do you get confused even at the initial setup

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like...

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the average rate of change of $f(x)$ on $[a,b]$ is by definition the quantity $\frac{f(b)-f(a)}{b-a}$ --- there isn't any special process to ``finding'' this aside from plug-and-chug.

obsidian monolithBOT
violet stratus
#

,w what is a histogram

obsidian monolithBOT
modest bolt
#

So it provides definitions too, didn't know that

echo sinew
#

,w Italy

obsidian monolithBOT
echo sinew
#

And not only math lol

violet stratus
#

,w pakistan

obsidian monolithBOT
violet stratus
#

yep

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double checked

prisma aurora
violet stratus
#

we need a discussion sub-group to test these bot functions

willow bear
#

do you mean: "the simplifying is easy; the setup is where i'm lost"?

prisma aurora
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sorry i was a little distracted

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i meant to say the simplifying and acc doing the algebra for it challenges me

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the set up is rather easy

willow bear
#

ok right

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so you're gonna need to deal with fractions no matter what kinda by design, but if the formula for f(x) itself includes fractions then you may also need to deal with nested/skyscraper fractions

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so if that is the case there's a trick you can do to make your own life somewhat easier

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one moment

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you still need to know how to work with fractions i.e. adding, subtracting, multiplying, maybe dividing fractions but this way is a bit easier @prisma aurora

alpine shore
#

Hello,I need help.

prisma aurora
heavy pewter
#

use a³-b³ 🤔

hidden birch
willow bear
modest bolt
#

Let 8+h=x³ → h=x³-8

hidden birch
willow skiff
# alpine shore

alternatively, use the definition of the derivative:

$$\lim_{x \to a} \frac{f(x) - f(a)}{x - a} = f'(a)$$

where $f(x) = x^{1/3}$, $x = 8 + h$, and $a = 8$

obsidian monolithBOT
prisma aurora
willow bear
#

no not yet

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i was gonna ask you now:

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do you see how to simplify $\frac{1}{h}\paren{\frac{1}{4+h}-\frac{1}{4}}$?

obsidian monolithBOT
willow bear
#

i can walk you through it if you need.

prisma aurora
#

no i still dont, im really weak on this stuff, ima give a guess though

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acc not a clue distrucbe or LCD?

hushed sphinx
#

You could start by putting the two fractions being subtracted on a common denominator.

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(This turns out to lead to progress, but it's such a natural thing to try that you should try it even if you cannot yet see whether it will make progress or not).

willow bear
prisma aurora
willow bear
#

anyway yes gonna reiterate

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when you see two fractions being added or subtracted a natural first step to simplification is often to combine them into one

prisma aurora
#

i see and say if it was with a variable as one the denominators, can i just multiply the two denominators to get a LCD

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In this case (4)(4+h)

willow bear
#

yes

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though you should be on the lookout for common factors generally to get the lowest common denom

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but in this case yes it's just the product

vagrant nymph
#

when in a question they say which of the following limits vanishes they mean which of the following limits is 0 right?

prisma aurora
#

i just wanted to say i really appreciate the help

willow bear
#

we don't distribute it no

vagrant nymph
willow bear
prisma aurora
willow bear
#

yes you should've

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"distribute" has a pretty specific meaning that should not be confused

prisma aurora
#

mb

vagrant nymph
#

in this question how do i comment about option a and b

zinc herald
#

what is the limit of f(x) as x-> infinity

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@vagrant nymph

vagrant nymph
#

(a/b)^inf

zinc herald
#

yes

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now what happens if a<b

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say a is 1 and b is 2

vagrant nymph
#

waiy mb i had doubtf in opt a and c

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if a<b limit is 0

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i am not sure about a and c

zinc herald
#

well does A make sense

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if a>b ?

vagrant nymph
#

if a>b than limit is infity

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so does that imply limit does not exist?

zinc herald
#

I am assuming that

vagrant nymph
zinc herald
#

typically, if it goes to infinity then it does not exist

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it's not any real value

vagrant nymph
#

alr thanksss i did not know that

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it matches with the answe tho

zinc herald
#

what

vagrant nymph
#

i got it now

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thanks @zinc herald

zinc herald
#

np

exotic barn
#

hey@dry verge, I hope you don't mind me sharing a solution

#

from the previous question

dry verge
exotic barn
#

It's okay!

obsidian monolithBOT
exotic barn
vagrant nymph
#

is my soln correct?

willow skiff
#

instead you should factor, so $\lim_{x \to 0} \frac{1}{x} \left(1 - \frac{x}{\tan x} \right) = \lim_{x \to 0} \frac{1}{x} \cdot (1 - 1)$

obsidian monolithBOT
vagrant nymph
#

hmm okay leeme try again

willow skiff
vagrant nymph
vagrant nymph
willow skiff
#

$\frac{0}{x} = 0$ except for $x = 0$ sure

obsidian monolithBOT
willow skiff
#

so that would be a removable discontinuity at x = 0

willow skiff
#

I'm just saying what you can't do is split apart the limits

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$\lim_{x \to 0} \frac{1}{x} - \lim_{x \to 0} \frac{1}{x}$: no!

obsidian monolithBOT
vagrant nymph
#

okay fair

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got it

#

thankss

willow skiff
#

np!

lament crag
#

im taking AP precalculus ima need alot of help this school year coming

willow skiff
woven meteor
#

how did u guys leanr pre calculus?

willow skiff
true geode
true geode
#

Vine reference

willow skiff
#

bruh.

true geode
#

(what it's a fokken goldmine of the Internet)

lean drum
vagrant nymph
#

how do i learn the expansions in limits

#

its like all of them are the same😭

modest bolt
#

Learn the pattern they aren't same

#

Instead of learning e^x=1+x+x²/2!+x³/3!...
Try to learn e^x=x^0/0! + x^1/1! + x^2/2! + x^3/3! ...

#

I think it's easy this way to remember

vagrant nymph
#

hmm yea ig that workss

#

also what am i doing wrong in this question

modest bolt
#

The question's wrong

#

Your answer seems right

winter comet
#

?

#

you crossed out -1/24 and sin^2(x)/(24 x^4)?

vagrant nymph
#

so that becomes 1/24x^2

winter comet
#

thats why you got an indeterminate form in the first place

vagrant nymph
#

or am i trippin

vagrant nymph
#

i have been doing taht

winter comet
vagrant nymph
#

hmm fair fair

#

than what do i do

winter comet
#

ig you could try expanding the sine terms 💀

modest bolt
#

Ok so got have 1)6

#

*gave 1/6

vagrant nymph
winter comet
#

yeah

vagrant nymph
modest bolt
winter comet
#

i would probably just expand cos(sin(x)) as a maclaurin series and cos(x) as well tho ngl 💀

#

which would require going back to the top butuh

modest bolt
vagrant nymph
winter comet
#

🫠

vagrant nymph
modest bolt
vagrant nymph
#

alr bet

#

ill do that

#

ahh i dont think we are going anywhere after expanding sin x

#

like thats not helping

#

any other thing we can do?

winter comet
#

as a maclaurin series

#

with the taylor series formula

vagrant nymph
#

macalaurin seriess?

#

taylore series formula?

#

idk any of this

winter comet
#

have you seen this before?

vagrant nymph
winter comet
#

bruh

vagrant nymph
#

we have not done much calcluas'

winter comet
#

so are you not supposed to use it then?

vagrant nymph
#

like the question is from my cocaching paper

#

sometimes they just give question out of syllabus

winter comet
#

they taught you just certain expansions but not the general formula for it ig? 🫠

vagrant nymph
modest bolt
#

You can still do it with cosx and sinx expansion

vagrant nymph
#

alr ill do it tmrw now

#

immgonna go sleep

lyric cradle
#

Why is the derivative of |sin x|-|cos x| discontinuous while the function itself is continuous?

summer ruin
#

continuity doesn't even imply the derivative exists at all

hushed sphinx
#

You don’t need the sine and cos to see this phenomenon -- |x| itself is a continuous function whose derivative has a undefined point with a jump discontinuity.

high pelican
#

i mean it turns out most are nice but still

#

you should know e^x in general tho its an easy one

river drift
#

<@&268886789983436800>

quasi pollen
#

we love taylor series but they sometimes dont work (sometimes)

alpine shore
#

I need help on this guys.

willow bear
#

... integration is not really precalculus, and i specifically redirected you to #calculus, but fine.

#

ok.

#

@alpine shore

#

ok you moved.

prisma aurora
#

guys yall think i can do pre cal over the summer? like level of difficulty?

final plaza
#

I think it’s possible

pastel lava
#

Hello guys

#

Quick question

willow bear
pseudo zealot
#

i skipped into calc bc!!

willow skiff
willow skiff
#

go leaping, jumping, and galloping into calc BC my man

tame pike
#

Do I replace -4x with -3/x?

uncut mulch
#

no

#

to get
f(g(x)),
replace all x in f(x) = sqrt(2-4x)
with g(x), (or -3/x)

tame pike
#

Ok

lime glade
# tame pike

I hope this is a funny representation on how to compose functions

It also helps to write out the outside function while replacing the variables with parenthesis and then go back to write the second function in the empty parenthesis

tame pike
#

Ok, thanks 🙏

modest bolt
lime glade
spice nymph
#

oreo
rooe

#

oooo

#

re

#

f(x)=oo

#

g(x)=re

#

(f g)(x)=oreo

#

(g f)(x)=rooe

#

literally functions.

elfin jay
spice nymph
vagrant nymph
#

Is there any way to solve this without making like so many cases

modest bolt
#

To confirm what I did was right or wrong, I am not very sure about this.

vagrant nymph
#

20

modest bolt
#

I was very wrong lol

vagrant nymph
#

a is 1 b is 4 c is 3

vagrant nymph
shell violet
#

hello guys hw can i write that all element of a set are from a list ?

shell violet
willow skiff
#

npnp

hoary iris
willow skiff
hoary iris
drifting oyster
willow skiff
#

I did a step-by-step here

#

it really helps, hearing from the person who was asking there

#

@vagrant nymph you'd probably appreciate a sol too

drifting oyster
#

I thought we were talking about the ceiling function and I was confused about the solution lol

willow skiff
#

yeah the name 'greatest integer function'

#

it's shorthand for greatest integer that is less or equal to x

drifting oyster
#

Ah so basically floor x

modest bolt
vagrant nymph
#

thankss @willow skiff

silk ermine
#

Guys

#

Geometry is betetr than calculus

vagrant nymph
silk ermine
vagrant nymph
silk ermine
lyric cradle
#

Does the integral of f(x) /dx signify something. How will such a integral be evaluated?

drifting oyster
lyric cradle
vagrant nymph
#

what is this question😭

hushed sphinx
#

You can either try to wing it by intuition, or actually compute the sets being compared.

lime glade
vagrant nymph
#

like id ont get this part

hushed sphinx
#

Would you understand it better as $g(A) = { x \in \bR \mid f(x) \in A }$?

obsidian monolithBOT
#

Troposphere

vagrant nymph
#

what does f(x)EA mean over here

#

like i understand the basic meaning

#

but we dont know what is A right

#

thiss is soo confusingg

hushed sphinx
#

The problem states that A is a subset of R.

#

So, a set of real numbers.

vagrant nymph
#

R is real numbers right?

#

yea okay

#

so basically g(x) is a set of some real numebrs?

hushed sphinx
#

I wouldn't write that, because that requires "x" to be a set of real numbers, which would be confusing.
The input to the function g is a set of real numbers. The output is also a (usually different) set of real numbers.

vagrant nymph
#

makes more sense

#

leeme try this question again

#

okay i gfot it

#

thankks @hushed sphinx

swift aurora
#

bro someone teach me about differentiation of anything other than constants, e^x, 1/x and x

#

i want to learn integrals but i need to know diffs before i start grade 12

hushed sphinx
#

"Teach me everything about so-and-so" is a very big ask for a live chat. There are entire books written about what you want to know (usually with "calculus" in the title); get one of those and start working through it.

swift aurora
#

right
thats a good start

empty otter
#

then do it for polynomials and rationals

#

then there's more that idk about

whole void
verbal geode
whole void
willow skiff
#

ah I checked

#

sine as a function is definitely Renaissance era mathematics

#

but you don't even need to define sine as a function

verbal geode
#

I think "it is"
Archimedes Polygon Method through Inequality got an answer for finding Pi of sin

verbal geode
#

Sry
My phone screen makes me trouble

#

The Answer is Geomtric Reasoning
I think "it is"

willow skiff
#

you can't use the polygonal method on sine

verbal geode
#

Yes

#

But what are other types that can be solved without calculus for Finding area

willow skiff
#

The method of exhaustion (Latin: methodus exhaustionis) is a method of finding the area of a shape by inscribing inside it a sequence of polygons (one at a time) whose areas converge to the area of the containing shape. If the sequence is correctly constructed, the difference in area between the nth polygon and the containing shape will become a...

#

there's this whole list

#

also Cavalieri's principle

#

In geometry, Cavalieri's principle, a modern implementation of the method of indivisibles, named after Bonaventura Cavalieri, is as follows:

2-dimensional case: Suppose two regions in a plane are included between two parallel lines in that plane. If every line parallel to these two lines intersects both regions in line segments of equal length,...

verbal geode
#

Oh
That method also Suits to be correct for Archimedes Polygon principle as well
As you said Specific Type of Geomtric Reasoning

willow skiff
verbal geode
#

Yup
It sounds correct rightv

hoary iris
#

Is $\lim_{x \to 0}(1+kx)^{\frac1x}=e^k$?

obsidian monolithBOT
#

Monkey•D•Luffy

hoary iris
#

I know that $\lim_{x \to \infty}\left(1+\frac{k}{x}\right)^{x}=e^k$

obsidian monolithBOT
#

Monkey•D•Luffy

hoary iris
hushed sphinx
hoary iris
#

Is it only $\lim_{x \to 0^+}(1+kx)^{\frac1x}=e^k$ and not $\lim_{x \to 0^-}(1+kx)^{\frac1x}=e^k$?

obsidian monolithBOT
#

Monkey•D•Luffy

drifting oyster
#

You run into some issues when approaching from the negative side...

#

Because 1/x will be negative

modest bolt
obsidian monolithBOT
modest bolt
#

Mine looks dull

bleak mantle
#

u mean gray

hoary iris
slender notch
#

Hello what do I do after this?

#

I modified a problem and now I do not know what to do haha

raw hill
slender notch
slender notch
raw hill
slender notch
#

I interpreted it as telescoping before 202

#

oh okay

raw hill
slender notch
#

Yep, the answer is ||1/1005 summation of 1/n||

#

Okay that did not make sense, hers an image

raw hill
#

You can also write this using the harmonic numbers

#

$\frac{H_{201}}{1005}$

obsidian monolithBOT
#

Civil Service Pigeon

raw hill
#

where $H_n=\sum^{n}_{k=1} \frac{1}{k}$

obsidian monolithBOT
#

Civil Service Pigeon

slender notch
#

NICE!!
THANK YOU!

hoary iris
#

Can we use any notational shorthand for limits like $L_{f(x)}=\lim_{x \to \infty}f(x)$ so that it means $L_{g(x)}=\lim_{x \to \infty}g(x)$ or $L_{f \circ g(x)}=\lim_{x \to \infty}f \circ g(x)$?

obsidian monolithBOT
#

Monkey•D•Luffy

hoary iris
#

Can we do something like this? or is there any other representation there for it? <@&286206848099549185>

modest bolt
#

Let l(f(x)) = lim x→∞ f(x).
Then, l(g(x)) = lim x→∞ g(x),
l(fog(x)) = lim x→∞ fog(x).

#

Won't this work breadthink

#

There's no reason to introduce new notation but ofc you can do it for your convenience, but idk if teachers in exam consider it correct or not

floral sigil
#

its a 2 letter difference 😭

obsidian monolithBOT
#

Monkey•D•Luffy

hoary iris
#

Ping me please if anyone has something to say to me for this!(Thank you!)

hoary iris
#

Not for the limit of f(x) = limit of g(x) but limit changing from e to 1

hoary iris
#

What is partial derivative?

royal oracle
winter comet
river drift
#

it's part of a total derivative :)

winter comet
winter comet
#

<@&268886789983436800> ?

#

almost pinged some guy called yamal

#

idk why @mode gave me yamal

safe basin
#

Now you gotta make yamal a mod whoever that is frfr

long tapir
#

Why is it 1?

#

They use squeeze theorem but i still dont understand how so

winter comet
#

sin(x) approximates x, and the error between them becomes 0 as x->0

long tapir
#

Sin(0) = 0

#

x = 0

#

Shouldnt it be 0/0?

#

And therefore require us to do more math?

winter comet
#

yes

long tapir
#

But if you did squeeze theorem wouldnt you just get

#

-1/x <= sin(x)/x <= 1/x

winter comet
#

that doesn't really give you any new information though

#

since lim x->0 1/x or lim x->0 (-1/x) doesn't exist

long tapir
#

Yeah

#

Im just confused as to how to solve the problem

winter comet
long tapir
#

Did not

#

I just know it apparently uses squeeze theorem

winter comet
#

there are other ways like maclaurin series or l'hopital but :l

winter comet
#

you want to find a function that you know is greater than sin(x)/x and one that is less than sin(x)/x right?

river drift
#

Courses on Khan Academy are always 100% free. Start practicing—and saving your progress—now: https://www.khanacademy.org/math/ap-calculus-ab/ab-limits-new/ab-1-8/v/sinx-over-x-as-x-approaches-0

Showing that the limit of sin(x)/x as x approaches 0 is equal to 1. If you find this fact confusing, you've reached the right place!

Watch the nex...

▶ Play video
old bane
#

How to find the range and domain of the natural log if there is an imaginary part (i) in it?

river drift
#

can you show the specific question you're working on?

old bane
#

ƒ(x)=sin{ln[5x^2 - 8x +4]}

river drift
#

so the logarithm is defined whenever the function inside is positive

old bane
#

its in iota

river drift
#

i assume you tried to solve 5x^2 - 8x + 4 = 0 and got a complex number solution

old bane
#

ya

river drift
#

but for our purposes, that means that the function is never equal to 0 in the real numbers

old bane
#

8+-4i / 10

river drift
#

so it's either always positive or always negative

hoary iris
pliant bluff
#

why are people using this channel for calculus :/

hoary iris
pliant bluff
#

and people were showing summation and stuff

#

literal integration aswell

hushed sphinx
# pliant bluff why are people using this channel for calculus :/

I think it is because it is the only channel in the Pre-University category that has "calculus" in its name, and people who are learning calculus in high school may have a misconception that they're not supposed to use the Early University channels for their questions.

pliant bluff
#

basics ofc

#

school didnt teach us reciprocals of trig functions

#

or limits during pre calculus

willow skiff
void charm
forest blaze
pliant bluff
#

..

#

why the hell did i not get caught them in trig

#

at least i know sin csc cos sec tan cot

#

literally inversely named

#

or thats hwo i see it

#

so i can remember that, but anything to do with identities we havent actually started trying to learn

#

istg if my school skips anything important its gonna put everyone behind while im waiting

void charm
hoary iris
pliant bluff
pliant bluff
hoary iris
#

Is summation also in calculus?

pliant bluff
#

we only got caught the 3 basics

#

i dont see how hyperbolic functions matter in precalculus

#

pls explain bro

#

also arcsin and stuff can go away

#

i dont like the derivatives of them

hoary iris
pliant bluff
#

i already know im not gonna like deriving with them

#

when i ever get there

#

the basic trig ones are easy, power easy, chain product quotient

#

ah yes, arc.

#

how about we get rid of those

#

and just use e^x

#

and lets change the world to base 6

hoary iris
#

trig is inevitable in our life lol

pliant bluff
#

roll of fake stream card scams

noble lava
pliant bluff
noble lava
#

Ignorance is bliss

shrewd leaf
#

yo yo yo i lust learned integration lol

noble lava
#

Did you like it?

#

Integration one of the most fun topics imo

shrewd leaf
#

yea its pretty cool, im just doing simple areas under graphs

noble lava
#

So definite indefinite are left

shrewd leaf
#

there alr but i cant do anything with them yet 🤷‍♂️

noble lava
#

O

shrewd leaf
#

got no idea how to use trig like sin and cos with integration lol

noble lava
#

It's fine dw

willow skiff
noble lava
#

Concentrate on area under the curve first

willow skiff
#

so if d/dx (sin x) = cos x

#

you know the integral of cos x = sin x + c

shrewd leaf
#

fair enough if you know one you can get the other but im not sure how to get one in the first place lol

shrewd leaf
#

or is that crazy stuff

willow skiff
#

so use the derivative definition, $\frac{d}{dx} \sin x = \lim_{h \to 0} \frac{\sin(x + h) - \sin(x)}{h}$

obsidian monolithBOT
willow skiff
#

use the compound angle identity

noble lava
#

Have you been taught limits yet?

willow skiff
#

then there's these two famous limits, $\lim_{h \to 0} \frac{\sin h}{h}$ and $\lim_{h \to 0} \frac{\cos h - 1}{h}$

obsidian monolithBOT
shrewd leaf
#

nah this is going straight over my head 😭

willow skiff
shrewd leaf
#

yea havent been taught that yet ima take a look lol

willow skiff
#

we found the issue congrats

noble lava
#

Lol if you havent been taught it dont confuse yourself

#

If we use limits its just gonna be to find a differentiation

#

And after that its integration

#

So would just muddle 3 chaps up for ya

shrewd leaf
#

ah ty

willow skiff
#

yeah also get a proper textbook while you're at it

#

like Thomas's Calculus

shrewd leaf
#

that might help yea 😅

willow skiff
noble lava
#

When you're at your peak

#

Like when you're done with 12th grade

#

I would suggest doing this

#

Uh

#

The peak of highschool math

shrewd leaf
willow skiff
noble lava
noble lava
#

Advanced i wouldnt say so

willow skiff
#

oh I see

noble lava
#

Advanced is more in depth application

willow skiff
#

no then you might as well dive into linear algebra

noble lava
#

Mains is speed solving

willow skiff
#

might as well learn proper 1st year uni maths

noble lava
#

True

#

But just as a challenge i tried the calculus section

#

Of the book above

#

💀

#

Took me like a month to finish

shrewd leaf
#

jesus i kinda thought i was good at maths 😭 it feels like it never stops getting harder lol

noble lava
#

Same

#

Its beautiful tho

#

So i try to keep learning

#

Even if its not in syllabus

sick fog
hidden sun
#

Anyone here did sheldon axler's precalculus

#

I'd be glad to know what book is the best continuation

hoary iris
#

@noble lava May I ask you a easy limit?(for fun)(If you're interested)

hoary iris
noble lava
#

1+x^4*(2-x)/x
2-x+2x^4-x^5/x
-1+8x^3-5x^4
=1/e

hoary iris
#

sorry its raised to the power of 2/x

noble lava
#

What

obsidian monolithBOT
#

Monkey•D•Luffy

hoary iris
noble lava
#

Oh wait

#

I did

#

A mistake

#

LMAO forgot formula

hoary iris
noble lava
#

Its 1

noble lava
hoary iris
noble lava
noble lava
hoary iris
hexed yarrow
#

! Help

tender questBOT
#

To ask for mathematics help on this server, please open your own help channel or help thread. See #❓how-to-get-help for instructions.

noble lava
#

This is not help

#

Its a challenge

hoary iris
#

us?

hoary iris
noble lava
hoary iris
#

Are you interested in giving me a limit?

noble lava
#

You just starting limits?

#

Or fairly proficient?

hoary iris
noble lava
hoary iris
noble lava
#

But youre done with all the 7 indeterminate forms?

hoary iris
hoary iris
#

lol idk

#

Can you give me limit in the inderminate form except 0/0 0 * infinity?

#

Cause I haven't seen any limits other than these indeterminate form

hoary iris
#

anyways Thank you for your time @noble lava !awoo

noble lava
#

Try 6th

#

Just a simple one to test

hoary iris
noble lava
#

Correct

#

Did you do lhospital?

hoary iris
#

nope

noble lava
#

Small angle?

hoary iris
#

divide by 2x on num and den

noble lava
#

Oh good one, standard results

hoary iris
noble lava
#

Fast af

hoary iris
noble lava
#

Small angle approximation means that sin x when x approaches 0 can be written as x

noble lava
#

Indeed

hoary iris
#

I love that approach

noble lava
#

Same for tan x btw

hoary iris
#

but not for cosine lol

noble lava
#

But for cos x when x approaches 0 its 1

#

So even better lol

hoary iris
#

Where did you find those questions?

noble lava
#

15 is a better one, try it if you want

noble lava
hoary iris
hoary iris
noble lava
#

You can do that but it doesnt help you get closer

#

Since its 0/0

#

So indeterminate

hoary iris
#

well if it is 0/7x^4

noble lava
#

Dont forget x is 0 so you need to put that in the denom, and its small angle approximation, not an exact value

noble lava
noble lava
#

I'm sure you're finding this to be a pain in the ass by lhospital opencry

noble lava
#

Try something else

#

Remember trigo

#

Large powers in the denom are generally a sign of using trigo formulae or series expansion

#

Ping when you have the answer or when you need a hint

noble lava
hoary iris
#

kongouderp @noble lava hint please

hoary iris
#

@noble lava 🫠

noble lava
#

Did you use my hint

hoary iris
noble lava
#

Do you remember the formula for cos C- cos D

hoary iris
noble lava
#

Oh its not been taught to you?

hoary iris
#

yes it is but I didn't think of that

#

rn

noble lava
#

Ah

hoary iris
noble lava
#

Always

#

The learning must never stop

#

Unless you're on vacation

#

In which case

#

It can

hoary iris
#

I haven't even thought of single step to this limit

noble lava
hoary iris
noble lava
#

Also this was sent by my instructor when we finished limits

#

Like one month b4 the end of grade 11 so we had almost finished determinants by then

hoary iris
hoary iris
#

What is this limit's level?

noble lava
#

(For jee)